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Entry type: Application example Entry ID: 43297078, Entry date: 11/10/2014

SINAMICS G120/G120P, CU230P-2: Closed-Loop Controlled Cooling Tower Fans

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Application description for the scripted commissioning of a SINAMICS G120 for a cooling circuit

Water and other cooling mediums are used in process technology and building systems in order to dissipate process heat or power loss in the form of heat. Cooling towers are used to cool down the hot cooling medium. For open circuit systems, the hot water is sprayed out through nozzles, routed through a mechanical cooler and collected in a basin or reservoir. For closed circuit systems, the cooling medium circulates through a plate-type cooler (heat exchanger). Air is used for the cooling - which flows upwards through the cooling tower. The air is either drawn in through fans at the top of the cooling tower or fans at the air intake and then forced through the cooling tower. A pump circulates the cooling medium in the cooling circuit.
The speed of the fan/fans can be controlled (closed-loop) by measuring the temperature of the cooling medium that flows out. At low cooling medium temperatures, only a low airflow is required; the fan rotates slowly and only blows air at a low rate. At higher cooling medium temperatures, the cooling airflow is increased, the fan now blows up to the maximum flowrate (volume flow) - and when the cascade circuit function is used, additional fans are switched-in.

The attached description is used to completely set the inverter parameters for the "fans to control the cooling circuit" application. In includes a standard connection circuit diagram for the control wiring, a script that can run in the STARTER commissioning software, as well as additional functions, which are used for subsequent parameterization.

Commissioning of SIMOTICS FD motors is not supported in this version.
When using load side components as output reactors, dv/dt filters and sinusoidal filters, necessary parameter changes have to be done additional.

for SINAMICS G120/G120P, CU230P-2 from FW V4.4
  Download (358,0 KB)
 Registrierung notwendig  STARTER Script (7,8 KB)

Last Changes
02/2014: Script and PDF revised for FW from V4.4
02/2017: Tested with Firmware V4.7 SP6 HF2 and STARTER V4.5.1.0

Additional Search terms: motioncontrol_apc_applications

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